Feature article published in the Tasmanian Year Book, 1998 (cat. no. 1301.6)

Contributed by Jayne Balmer, Botanist, Tasmanian Parks and Wildlife Service

Kings Lomatia (Lomatia tasmanica), formerly called Kings Holly, is an unusual shrub that grows along creek banks in the cool, dense, rainforest of Tasmania’s remote Wilderness World Heritage Area. It is one of many Tasmanian endemic plants that helped to have the area listed as World Heritage.

Kings Lomatia was discovered by the miner and naturalist Denny King. Described and named in the 1960s, it is a member of the Proteaceae family. A spindly, straggling plant growing up to five metres tall, Kings Lomatia has attractive leaves forming whorls at the branch ends. Typical of other Proteaceae, it has clusters of rusty red flowers which resemble those of its relative, the grevillea. The plant does not appear to be able to produce seed, and is only able to regenerate itself by vegetative means, sending out long root stems from which new trunks arise.

Extensive searches have revealed that Kings Lomatia is naturally restricted to one small water catchment. There are only about 500 individuals and the area they inhabit is at risk from disease and fire, making the species vulnerable to extinction. The rarity of this plant has perplexed scientists.

The Parks and Wildlife Service has been co-ordinating research on the plant to assist with its long term conservation management within the World Heritage Area. Funds from the Australian Flora Foundation assisted with propagation research at the University of Tasmania. The Royal Tasmanian Botanical Gardens now have a propagation program, with the aim of making the plant commercially available to the public.

Genetic work undertaken at the University of Tasmania showed that there was absolutely no genetic variation within the population. Even plants separated by more than a kilometre were identical. The entire population is composed of a single plant clone. A study of the plant’s chromosomes revealed that Kings Lomatia is triploid, that is, it has three sets of chromosomes instead of two. Because of this it is unable to sexually reproduce. The plant is a rare freak of nature whose origins and age are as yet unknown.

It is now believed that this plant clone is the oldest known clone in the world. Radiocarbon dating of a charcoal sample found in the same sedimentary layer as a fossilized leaf of Kings Lomatia suggests that it has been around for at least 43,600 years. Whilst no genetic tests were done on the fossil leaf-which would prove that the two plants are indeed clones-the fossil and modern leaves have the same shape and epidermal cell structure. If the ancient plant were not a triploid these would look different. In comparison, a sterile, vegetatively reproducing, triploid cannot undergo any genetic variation.

This discovery is fascinating because it shows that even without the flexibility of genetic variation some plants are able to tolerate change. Kings Lomatia has lived through the major climatic change at the end of the last glacial, and survived the arrival of people in Tasmania.